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March 7, 2000 (Atlanta) -- NASA technology originally used to assess airflow over airplane wings has been used successfully in clinical trials to measure fetal heart rates in high-risk pregnancies. The new monitor is noninvasive and, compared with older monitors, more affordable, more portable, and easier to use, according to the NASA researchers.
Researchers at NASA worked with Veatronics Inc., in Charlotte, N.C., to convert the aerospace application into a medical device. The company has NASA's permission to license one or more commercial products based on this technology.
Allan Zuckerwar, DrSci, co-inventor of the device, tells WebMD that it is an electronic stethoscope with seven sensors made of a very flexible polymer film. The sensors are attached to a belt which the pregnant woman wraps around her abdomen. The monitor offers continuous surveillance, and the information is transmitted over the Internet to another site where there is a physician or a nurse waiting to examine the results. The monitor has software that interprets the heart rate and sets off an alarm when it is too fast or too slow.
The technology has several advantages, according to Zuckerwar, a senior research engineer at Langley Research Center, NASA, in Hampton, Va. One advantage is that, because it is flexible, it more easily conforms to the test surface than do heart monitors made of ceramics. Another advantage of the new monitor is its sensitivity. Because it has seven sensors, the new monitor can select the sensor that generates the best signal. This is helpful because the fetal heart tone is very local. "It's so localized that you might detect the tone on one sensor but not on the adjacent sensor," says Zuckerwar.
Other advantages of the new heart monitor are its ease of use and its portability, says Zuckerwar. "[In comparison,] the ultrasonic equipment [used in older monitors] is too sophisticated and isn't very easily portable, and the mother would have to be supervised very closely," he says. "Our instrument is easy to use. ... The idea is for mom to be able to perform the test on a daily basis at a time when it's convenient for her ... instead of [coming into the clinic] twice weekly. The frequency of surveillance is greatly increased from semiweekly to daily."
"It's a technology that we are bringing to the patient as opposed to the patient having to come to the technology," says Kevin Gomez, MD, who has conducted NASA-sponsored clinical trials at Morehouse School of Medicine in Atlanta, and continues the trials at Atlanta Perinatal Associates.
"If this [new technology] is more practical or equally practical and less expensive [compared with ultrasound], it'll find its way into the marketplace," says Richard Paul, MD, professor of obstetrics and gynecology at the University of Southern California Keck School of Medicine, in Los Angeles. And, according to Gomez, the new monitor is considerably less expensive than ultrasound.
Not only will the new technology benefit people in rural settings where they cannot access physicians, says Gomez, but it should be able to benefit patients from urban centers, where they may be unable to keep their appointments.
"As far as the safety, we haven't seen any problems," says Gomez. "Nor would be we expect to [see any]." Paul explains, in an interview seeking objective commentary, that the new device may also be able to remove some of the artifact interference, or background noise, because of its snug fit against the abdominal wall.
Gomez explains that, in the clinical trials, over 50 women who had high-risk pregnancies and who would normally have required fetal heart monitoring were simultaneously monitored with ultrasound as well as with the new heart monitor. The findings have been that the recordings from the new heart monitors look just like those produced by the ultrasonic equipment, he says. "Anything that you could put on the abdominal wall that would work reliably would probably be an improvement over the current ultrasound, which is probably 90-95% reliable," says Paul. "If you could get something that is 100%, that is all the better."
"Hopefully, within the next 6 months we should be ready to approach the FDA to try to see about getting approval for its use," says Gomez. "That is really the next step. We are fine-tuning things, and we'll hopefully have something that is going to be on the market within the year."